Substrate container with fluid-sealing flow passageway

ABSTRACT

A substrate container includes an enclosure and an access structure formed in the enclosure and providing fluid access through the enclosure to an interior of the substrate container. The access structure includes an opening and an inner surface. A grommet is situated against the inner surface of the access structure.

RELATED APPLICATION

This application is a divisional of application Ser. No. 11/108,619filed Apr. 17, 2005, which claims the benefit of U.S. ProvisionalApplication No. 60/563,528 filed Apr. 18, 2004, each of which is herebyfully incorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to substrate containers. More particularly, theinvention relates to substrate containers that include a flow passagefor a fluid.

BACKGROUND OF THE INVENTION

In general, carriers are utilized for transporting and/or storingbatches of silicon wafers or magnetic disks before, during and afterprocessing of the disks or wafers. The wafers can be processed intointegrated circuits and the disks can be processed into a magneticstorage disks for computers. The terms wafer, disk, or substrate areused interchangeably herein and any of these terms can refer tosemiconductor wafers, magnetic discs, flat panel substrates, and othersuch substrates, unless otherwise indicated.

The processing of wafer disks into integrated circuit chips ofteninvolves multiple steps where the disks are processed at variousprocessing stations, and stored and transported between processingsteps. Due to the delicate nature of the disks and their susceptibilityto contamination by particles or chemicals, it is vital that they areproperly protected throughout this procedure. Wafer containers have beenused to provide this necessary protection. Additionally, since theprocessing of disks is generally automated, it is necessary for disks tobe precisely positioned relative to the processing equipment for therobotic removal and insertion of the wafers. A second purpose of a wafercontainer is to securely hold the wafer disks during transport. Theterms wafer containers, carriers, cassettes, transport/storage bins, andthe like, are used interchangeably herein unless otherwise indicated.

During processing of semiconductor wafers or magnetic disks, thepresence of or generation of particulates presents very significantcontamination problems. Contamination is accepted as the single largestcause of yield loss in the semi-conductor industry. As the size ofintegrated circuitry has continued to be reduced, the size of particleswhich can contaminate an integrated circuit has also become smallermaking minimization of contaminants all the more critical. Contaminantsin the form of particles may be generated by abrasion such as therubbing or scraping of the carrier with the wafers or disks, with thecarrier covers or enclosures, with storage racks, with other carriers orwith processing equipment. Additionally, particulates such as dust canbe introduced into the enclosures through the openings or joints in thecovers and/or enclosures. Thus, a critical function of wafer carriers isto protect the wafers therein from such contaminants.

Containers are generally configured to axially arrange the wafers ordisks in slots, and to support the wafers or disks in slots, and tosupport the wafers or disks by or near their peripheral edges. Thewafers or disks are conventionally removable from the containers in aradial direction upwardly or laterally. The containers may have a shellportion with a lower opening, a door to latch into the lower opening,and a discrete carrier that rests on the door. This configuration, knownas SMIF pods, is illustrated in U.S. Pat. Nos. 4,995,430 and 4,815,912,both owned by the owner of the instant application and both incorporatedherein by reference. Additionally, wafer carrier assemblies can havefront openings with doors that latch onto front openings, which areknown as FOUPs or FOSBs, and are described in, for example, U.S. Pat.Nos. 6,354,601, 5,788,082 and 6,010,008, all of which are incorporatedby reference herein. In certain configurations, the bottom covers ordoors, front doors or the container portions have been provided withopenings or passageways to facilitate the introduction and/or exhaustionof gases such as nitrogen or other purified gasses, into the wafercarrier assemblies to displace ambient air that might have contaminants.

Previous containers have employed filter plugs to reduce the amount ofparticular contaminants that enter the container assemblies duringpurging. However, conventional attachment and sealing between theoperation element, i.e. the filter, and the housing of the seal is bythe way of rigid plastic housings and o-rings. Wafer containers known inthe art have also utilized various connection or coupling mechanisms forfluidly interfacing the flow passageways of the wafer containers tofluid supply and pressure or vacuum sources. Such attachment and sealingrequires specialized components which may be of complex configuration.

SUMMARY OF THE INVENTION

An improved wafer container according to one aspect of the inventionincludes a an enclosure portion with an open side or bottom, a door tosealingly close the open side or open bottom and defining an enclosureor container, and a plurality of wafer support shelve contained withinthe container. The door couples with the enclosure portion to form acontinuous enclosure that isolates the wafer carrier or other substratefrom the ambient atmosphere. The container has at least one accessstructure defining a flow conduit into and out of the enclosure. Asealing grommet is situated within the access structure in a fluid-tightengagement. An outer surface of the grommet establishes a generallyfluid-tight seal against an inner surface of the flow conduit. In oneembodiment, the grommet defines a flow passageway such as, for example,a cylindrical bore. In a related embodiment, the grommet includes acontact surface that can facilitate a fluid-tight coupling between theinterior volume of the wafer container and a nozzle or nipple for afluid or vacuum source. The grommet's interior sealing surface maydefine the flow passageway.

Optionally, the flow passageway through the grommet includes at leastone operational element substantially or totally contained therein. Theoperational element can be any component, subassembly, or device thatcouples or interfaces the interior volume of the wafer container to theexterior. Examples of operational elements include valves, filters,sensors, plugs, or combinations thereof. The operational element is influid-tight engagement against the interior sealing surface.

In operation, according to one embodiment, the grommet maintains a sealagainst the access structure to prevent undesired chemicals orparticulates from entering into the interior of the wafer containerassembly. Thus, any flow of fluid between the interior and exterior ofthe wafer container is limited to passing through the passageway definedby the grommet. Types of fluid flows include the introduction of purginggases such as, for example, nitrogen into the interior of the wafercarrier assembly.

The fluid flow can be further limited by the operational element. Forexample, where the operational element is a particulate filter, gaspassing through the passageway must also pass through the filter. Inanother example case where the operational element is a check valve, thefluid flow passing through the passageway is further limited to flowingin a specific direction. In one embodiment, the flow passageway throughthe grommet includes a filter and a check valve. In this embodiment,both functions, filtering, and flow direction assignment, are carriedout. In the another example embodiment, the operational element is aremovable plug, in which case no fluid is permitted to flow through thepassageway when the plug is inserted.

In another example embodiment, the operational element includes asensor. Types of useful sensors include temperature sensors, flow ratesensors, pressure sensors, gas concentration sensors, materialdetectors, and proximity sensors. Among these, and other sensors used asoperational elements, some (such as flow sensors) may permitflow-through, while others (such as pressure sensors) function also asplugs.

In manufacturing, the use of uniform sizing of access structures,sealing grommets, and operational elements, permits modularization.Thus, for a product line of various wafer containers, each havingspecialized operational elements, the wafer container assembly housingscan have a limited number of identical enclosure components with accessstructures positioned in a plurality of points throughout the commonenclosures. Each access structure can have a sealing grommet, some ofwhich are a blanking type (without a passageway), while other accessstructures can have sealing grommets with various integral operationalelements. Sealing grommets can be pre-assembled with various operationalelements and stocked as operational cartridge subassemblies.

An advantage and feature of preferred embodiments of the invention isthat the grommet configuration provides an elastomeric element that isgenerally of a cylindrical configuration with a bore extendingtherethrough, the bore itself having a cylindrical configuration. Thebore being of sufficient length to contain totally or substantially theentire length of an operational component inserted therein. The grommetpreferably has at least one planar surface arranged to be normal to theaxis of the grommet. Such surface can be utilized to effectively providea seating surface for a nipple or nozzle as part of a purging system.Volumetrically, the grommet is preferably larger that the operationalcomponent container therein. The grommet preferably has a crosssectional area taken in an axial plane whereby the cross sectional areaof the grommet is greater that the cross sectional area of the openingextending axially therethrough. The grommet preferably has a axiallength that is greater than the diameter of the opening or boreextending axially through the grommet. Whereas an o-ring generally has acircular cross section, the grommet herein has a non circularcross-section and cylindrical inner facing surfaces, cylindrical outerfacing surfaces, and planar end surfaces.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1A is an exploded perspective view of a wafer container assemblycomprising a wafer carrier, a bottom cover and an enclosure portion.

FIG. 1B is an exploded perspective view of another embodiment of a wafercontainer assembly comprising a wafer carrier, side cover and anenclosure portion.

FIG. 2 is a bottom view of an example bottom cover showing structurelocated on the bottom surface of the bottom cover.

FIG. 3 is a diagram illustrating an example grommet and exampleoperational element according to one embodiment of the presentdisclosure.

FIG. 4 is an exploded perspective view of an example cover or door for awafer container assembly that includes sealing grommets and operationalcomponents.

FIGS. 5A-5B illustrate the construction of example operationalsubassemblies, each incorporating a grommet and at least one operationalelement.

FIG. 5C illustrates an example assembly of an operational subassemblyinto a flow conduit.

FIGS. 6A and 6B are cross-sectional views illustrating a gas purgingarrangement according to one embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1A illustrates an example wafer container assembly 100 thatincludes wafer rack 102, bottom section 104 and enclosure portion 106.Bottom section 104 is adapted to sealably couple with enclosure portion106 to define an interior space which can isolate wafer carrier 102 fromambient atmosphere 108. As shown in FIG. 1, wafer carrier 102 cancomprise a plurality of elements 110 that can hold and position aplurality of silicon wafers within wafer carrier 102. Generally,elements 110 hold and position the silicon wafers such that contactbetween adjacent wafers is minimized, which can reduce damage to thewafers that can occur during processing and/or transportation ofsilicone wafers. FIG. 1B illustrates another configuration of a wafercontainer assembly 103 known as a FOUP or FOSB comprising an open front104, a front door 105 and enclosure portion 107. Wafers W are removedhorizontally through the open front. Slots formed in the interior sideshold the wafer. Front door 105 with seal sealingly engages withenclosure portions 107 to form an interior space that is isolated fromthe ambient atmosphere. The structure of a wafer carrier is describedin, for example, U.S. Pat. No. 6,428,729 to Bhatt et al., entitled“Composite Substrate Carrier,” which is hereby incorporated by referenceherein. Additionally, wafer carrier assemblies having front openingswith doors that latch onto front openings, known as FOUPs or FOSBs, aredescribed in U.S. Pat. Nos. 6,354,601, 5,788,082, 6,010,008, all ownedby the owner of the instant application and all hereby incorporated byreference herein. Receiving structure 109 for the grommets 124, 125 maybe in the bottom wall of the enclosure portion.

Referring to FIG. 2, an example wafer container section 120. In one typeof embodiment, section 120 is a side cover, bottom cover, or door of awafer container. In other type of embodiment, section 120 is anon-removable, non-openable wall section. Section 120 is illustratedcomprising access structures in the form of openings 122, 123, grommets124, 125 situated in openings 122, 123 and a plurality of statusopenings 126. Generally, the plurality of status openings 126 can belocated at desired positions on cover section 120 to provide a structurefor sensors, such as probes or other monitoring elements, to interfacewith the wafer container. For example, the interface between a sensorand a particular status opening 126 can provide information about thestatus of a wafer processing step or the like.

In one example embodiment, opening 122 facilitates fluid transfer intosection 120, which can facilitate the introduction of gases and otherfluids into the interior of the wafer container. Similarly, opening 123provides fluid transfer out the wafer container through section 120 suchthat gas or fluid located within the wafer container can be vented tothe ambient atmosphere. Thus, in this embodiment, opening 122 is aninlet, while opening 123 is an outlet. Although FIG. 2 illustrates anembodiment where section 120 comprises two openings 122, 123,embodiments having four, five, six, or more access structures located insection 120 are contemplated and are within the scope of the presentdisclosure.

As illustrated in FIG. 2, grommet 124 is positioned within opening 122to seal opening 122, and grommet 125 is positioned within opening 123 toseal opening 123. As described below, grommets 124, 125 each creates aseal against the interior of their corresponding opening 122, 123, andprovides at least one bore or passageway through the grommet. In oneembodiment, the bodies of grommets 124, 125 each have a cross-sectionalshape that corresponds with the interior features of openings 122, 123,and is sized to seal and substantially occlude its corresponding opening152, 153. One of ordinary skill in the art will recognize that thecross-sectional shape and size of openings 122, 123 can be guided bysize gas flow requirements, and operating pressures of a particularwafer container assembly. In a related embodiment (not shown), grommet124 includes two distinct passageways.

FIG. 3 illustrates one example embodiment of grommet 124, 125. Grommet124, 125 according to this embodiment has a generally cylindrical body128. In one type of embodiment, body 128 is formed from rubber,silicone, or other elastomer or polymer having desired sealingcharacteristics. Optionally, body 128 includes sealing features 130 inthe form of ring-shaped protrusions circumferentially situated along theexterior of the cylindrical wall. Grommet 124, 125 also includes bore132 passing through the center of body 128. The interior surface of body128 that defines bore 132 optionally includes sealing features (notshown) for sealing against operational element 134 situated at leastpartially within bore 132.

In one example embodiment, operational element 132 is a valve such as acheck valve. In another example embodiment, operational element 132 is afluid filter. In another embodiment, operational element 132 is asensor, such as a temperature sensor, flow rate sensor, pressure sensor,gas concentration sensor, material detector, or proximity sensor. Inanother embodiment, operational element 132 is simply a plug to preventfluid travel through flow passageway 204.

FIG. 4 illustrates an example cover section 150. Cover section 150includes cover enclosure 170, latch elements 172, 174, cam 176 and outercover section 178. Cam 176 is connected to latch elements 172, 174 suchthat rotation of cam 176 actuates latches 172, 174, which causesprotrusions 180 to extend through openings 182 located in housing 170and lock housing 170 to another enclosure section (not shown). Outercover 178 is assembled over latch elements 172, 174 and cam 176. Coversection 150 also includes access structures 160, 161. Access structure160 includes inlet opening 152 and flow conduit 157. Access structure161 includes outlet opening 153 and flow conduit 158. Flow conduits 157and 158 each have a generally cylindrical wall having a height thatextends through the thickness of cover section 150 from the exterior ofthe wafer container to the interior.

Flow conduits 157 and 158 retain operational subassemblies 162 and 163,respectively. FIGS. 5A and 5B illustrate operational subassemblies 162and 163 in greater detail. Operational subassembly 162 is an inletsubassembly and includes grommet 154 having body 202 and bore 205.Operational subassembly 162 further includes check valve 211 installableinto bore 204, and filter 210. Embodiments of filter 210 includeparticle filters of suitable technology, such as HEPA filtration, or thelike. Operational subassembly 163 is an outlet subassembly that includesgrommet 155 having body 203 and bore 205. Optionally, operationalsubassemblies 162, 163 are each pre-assembled with their respectiveconstituent components as operational cartridges.

FIG. 5C illustrates the assembly of operational subassembly 162 intoflow conduit 157. Filter 210 is retained in place between the bottom ofgrommet 154 and retaining surface 164 of flow conduit 157. Grommet 154fits within flow channel 157 and forms a seal with the interior wall offlow channel 157. Check valve 211 fits sealably within flow passageway204 through grommet 154, and is aligned so that flow is permitted in thedownward direction as indicated in FIG. 5C.

As described above, openings 152, 153 in cover section 150, or in anyother enclosure portion, such as section 120 of a wafer containerassembly, can be sealed by the grommets of the present disclosure. Inone embodiment, the grommets include a body having a bore located withinthe housing, the bore extending along the major axis of the housing.Additionally, the embodiments of grommets of the present disclosure cancomprise an operation element located with the bore. The operationelement can comprise a check valve that can regulate the flow of gas orother fluids through the bore, a filter, a sensor or combinationsthereof. The check valves employed in the present disclosure can beoriented within the bore such that the grommets can be used to seal bothinlet and outlet openings on wafer carrier doors and/or enclosures.Additionally, as described below, the design of the grommet body canfacilitate sealing of the opening without the need for a additionalo-rings attached to the grommet. Furthermore, embodiments of grommets ofthe present disclosure can combine a grommet body, check value and/orfilter into an integral cartridge, which can improve the overall sealingability of the grommets and can facilitate easier construction of wafercarrier assemblies. In some embodiments, the grommets have an axialheight from about ⅛ inch to about 1 inch, while in other embodiments thegrommets can have an axial height from about ⅜ inch to about ¾ inch.Additionally, embodiments of grommets of the present disclosure can havea diameter from about ¼ inch to about 1.5 inches, while in otherembodiments the grommets can have a diameter from about 12 inch to about¾ inch. One of ordinary skill in the art will recognize that additionalranges of axial height and diameter of the grommets are contemplated andare within the scope of the present disclosure.

The grommets can be distinguished from O-rings known in the art in anumber of ways. For example the grommet configuration provides anelastomeric element that is generally of a cylindrical configurationwith a bore extending therethrough, the bore itself having a cylindricalconfiguration. The bore being of sufficient length to contain totally orsubstantially the entire length of an operational component insertedtherein. The grommet preferably has at least one planar surface arrangedto be normal to the axis of the grommet. Such surface can be utilized toeffectively provide a seating surface for a nipple or nozzle as part ofa purging system. Volumetrically, the grommet is preferably larger thatthe operational component container therein. The grommet preferably hasa cross sectional area taken in an axial plane whereby the crosssectional area of the grommet is greater that the cross sectional areaof the opening extending axially therethrough. The grommet preferablyhas a axial length that is greater than the diameter of the opening orbore extending axially through the grommet. Whereas an o-ring generallyhas a circular cross section, the grommet herein has a non circularcross-section and cylindrical inner facing surfaces, cylindrical outerfacing surfaces, and planar end surfaces.

FIGS. 6A and 6B are cross-sectional views illustrating a gas purgingarrangement according to one embodiment of the present disclosure.Example grommets 300 and 302 are situated in respective accessstructures 304 and 306 of an example wafer container having an interior308 and exterior 310. Access structures 304, 306 are formed within awall or door 312 of the wafer container, and each functions as a purgingport. Access structure 304 includes a retaining structure 314 that has ageometry specially adapted to sealably engage grommet 300. Likewise,access structure 306 includes a retaining structure 316 that has ageometry adapted to engage with grommet 302. Grommets 300 and 302 eachhave various sealing features 318, 320 for creating fluid-tight contactwith certain interior surfaces of retaining structures 314 and 316,respectively, as indicated.

FIG. 6A illustrates an inlet arrangement; whereas FIG. 6B illustrates anoutlet arrangement. For each arrangement, the direction of the flow isindicated. The inlet arrangement of FIG. 6A also includes filter 322situated and fluidly sealed between the contacting surfaces of grommet300 and retaining structure 314. The inlet arrangement of FIG. 6A alsoincludes a one-way valve assembly 324 positioned to permit fluid travelonly in the indicated flow direction. Analogously, the outletarrangement of FIG. 6B includes a one-way valve assembly 326 positionedto permit fluid travel only in the flow direction indicated. Valveassemblies 324, 326 are fluidly sealed within respective flowpassageways 328, 330 defined by the bores of grommets 300, 302. Grommets300, 302 have retaining features 332, 334 for securely holding valveassemblies 324, 326 in place within respective flow passageways 328,330. In one type of embodiment, one-way valves 324, 326 comprise valvebodies 336 and 338, outer seal rings 340 and 342, inner seal rings 344and 346, moveable pistons 348 and 350, and biasing springs 352 and 354.

In operation, the inlet and outlet arrangements can function in concertduring a purging activity in which existing air or gas within theinterior 308 of the wafer container is displaced by newly introducedair, gas, or other fluid. In one embodiment, as illustrated in FIG. 6B avacuum source 360 is coupled to the interior volume 308 by a outletnozzle 362. Outlet nozzle is adapted to interface with a contact surface364 of grommet 302. When downward force is exerted by the outlet nozzleinto grommet 302, grommet 302 compresses, but maintains its seal againstthe sealing inner surfaces of retaining structure 316 and against theouter surface of valve assembly 326. In one embodiment, the sealsbetween grommet 302 and retaining structure 316 and valve assembly 326are actually improved or made more effective by the downward forceapplied onto grommet 302 by outlet nozzle 362.

As the vacuum 360 is coupled with the interior volume 308, existingfluid in volume 308 is drawn out of the wafer container through theoutlet of FIG. 6B, while replacement fluid is drawn in through the inletof FIG. 6A, including through filter 322. In a related embodiment (notshown), a replacement fluid source (not shown) is coupled with interiorvolume 308 via an inlet nozzle having similar geometry with outletnozzle 362 and coupled with inlet grommet 300 in the same manner inwhich outlet nozzle 362 is coupled with outlet grommet 302. In anotherembodiment (not shown), no outlet nozzle is coupled with grommet 302,and the inlet nozzle carries pressurized replacement fluid into theinterior volume 308. In this embodiment, the displaced fluid simplyexists through the outlet arrangement of FIG. 6B

Generally, grommets 300, 302 can have the same cross-section shape asthe opening in which the grommet is designed to seal. For example, inone embodiment, grommets 300, 302 have a generally cylindrical shapewith a generally circular cross-section. However, one of ordinary skillin the art will recognize a variety of grommet body geometries arewithin the spirit of the present disclosure.

In one embodiment, grommets 300 and 302 are identical parts. In arelated embodiment, valve assemblies 324 and 326 are identical parts.Thus, in one type of embodiment, the components of the presentdisclosure can be used to seal both inlet and outlet openings using thesame component elements.

In another embodiment, grommets of the present disclosure can furtherinclude additional retaining features (not shown) for securely holding afilter such as filter 322 in the same or similar manner in whichretaining features 332, 334 retain valve assemblies 324, 326. Thus, apre-assembled operational subassembly can incorporate a grommet, a valveand a filter into a integral subassembly.

The grommet body, flanges and other components of the grommets of thepresent disclosure can be composed of any material suitable for use insemi-conductor processing applications including polymers andelastomers. In some embodiments, the grommet body and flanges can becomposed of a fluoroelastomer. Examples of fluoroelastomers are soldunder the trade name Viton® by Dupont Dow Elastomers. Additionally, insome embodiments, the elastomeric grommet body or grommet can have afluoropolymer, or other inert polymer, coated onto to the surface of thegrommet to isolate the elastomeric substance from the interior of thesubstrate container. Generally, the polymer or fluoropolymer coatingshould have some flexibility such that the sealing characteristics ofthe elastomeric grommet body are maintained.

The embodiments above are intended to be illustrative and not limiting.Additional embodiments are within the claims. Although the presentinvention has been described with reference to particular embodiments,workers skilled in the art will recognize that changes may be made inform and substance without departing from the spirit and scope of theinvention.

What is claimed is:
 1. A substrate container, comprising a containerportion with an open side or bottom, a door to sealingly close the openside or bottom, one of the door and the container portion comprising afirst access structure; and a first elastomeric grommet formed ofelastomeric material, the grommet having an axis, the grommet retainedin the access structure for providing fluid access to an interior of thesubstrate container, wherein the access structure defines an openingpassing from interior the container to exterior the container, andwherein the access structure has an apertured wall extending transverseto the axis of the grommet and the access structure further has anaxially extending wall with an inwardly facing surface sealingly engagedwith the elastomeric material of the grommet therein, and wherein thefirst elastomeric grommet having generally a cylindrical shape or atapered cylindrical shape, an axial length, an outer facing surfaceengaged with the inwardly facing surface of the axially extending wallof the access structure, an inwardly facing surface defining an openingconfigured as a bore extending axially through the grommet, and a pairof parallel and planar end faces arranged perpendicular to the axis, thegrommet when viewed in cross-section taken axially coincident with theaxis, having a cross-sectional area of the grommet that is greater thanthe cross-sectional area of the bore extending axially through thegrommet, each of the pair of end faces formed of elastomeric materialand one of the pair of end faces exteriorly exposed with respect to thesubstrate container for engaging with a purging nozzle, the substratecontainer further comprising a check valve positioned in the bore of thegrommet and a filter positioned intermediate the grommet and theapertured wall; and whereby the grommet provides a single body with acontinuous surface including an elastomeric sealing surface for sealingwith the access structure, an elastomeric surface for sealing with thecheck valve in the bore, and an exposed elastomeric surface for sealingwith an exterior purging nozzle.
 2. The substrate container of claim 1,further comprising a second access structure formed in the enclosure anda second elastomeric grommet, the grommet having an axis, retainedtherein for providing fluid access through the enclosure betweenexterior and interior of the substrate container, wherein the secondaccess structure defines an opening passing from interior the containerto exterior the container, and wherein the access structure further hasan axially extending wall with an inwardly facing surface for engaging agrommet therein and an apertured wall extending transverse to the axisof the second elastomeric grommet, and further the second elastomericgrommet having a shape corresponding to the first elastomeric grommetand having an outer facing surface confronting the inwardly facingsurface of the second access structure with a filter positionedtherebetween.
 3. The substrate container of claim 1, wherein the grommethas outer radii measured radially between the axis and the outer facingsurface, said outer radii measured for the entire axial length of thegrommet and for each outer radius the grommet has a radial thicknessmeasured between the inwardly facing surface of the grommet and theouter facing surface of the grommet, and for at least most of the axiallength of the grommet, each radial thickness comprises most of therespective outer radii.
 4. The substrate container of claim 1, whereinone end face of the grommet is an exteriorly exposed planar end face andthe other end face is an interiorly positioned opposite planar end faceand the operational element is a check valve and is positioned entirelybetween the respective end faces.
 5. The substrate container of claim 1,wherein the opening configured as a bore has a cylindrical shape andextends from one end face of the grommet to the other end face.
 6. Thesubstrate container of claim 5, wherein the axial length of the grommetis greater than the diameter of the opening configured as a bore.
 7. Thesubstrate container of claim 1 wherein the filter is constrained inplace by said grommet.
 8. The substrate container of claim 1, whereinone of the end faces of the grommet is an exteriorly exposed planar endface providing a sealing surface for a nozzle or nipple as part of apurging system without using o-rings.
 9. The substrate container ofclaim 1, wherein the grommet includes an exteriorly exposed contactsurface that can facilitate a fluid-tight coupling between the interiorvolume of the substrate container and an external purging system. 10.The substrate container of claim 1, wherein the grommet includes a bodyhaving at least one feature facilitating sealing with an externalpurging member.
 11. A substrate container, comprising: a purging porthaving a generally cylindrical or tapered cylindrical wall surroundingan opening and an apertured wall; an elastomeric grommet comprisingelastomeric material, the grommet having a generally cylindrical outersurface or tapered cylindrical outer surface and opposite planar endfaces, one of the two end faces providing elastomeric material outwardlyexposed with respect to the substrate container thereby providing apurging nozzle engagement surface, the grommet sealingly situated withinthe purging port with the elastomeric material sealingly engaged withthe cylindrical or tapered cylindrical wall, the elastomeric grommetincluding a bore extending from interior the substrate container toexterior of the substrate container providing a fluid flow paththerethrough, the bore having a bore surface with exposed elastomericmaterial; and an operational component sealingly situated substantiallywithin the bore, the operational component comprising a one way checkvalve, the operational component sealingly engaged with the elastomericmaterial in the bore of the grommet; and a filter positioner between thegrommet and the apertured wall; whereby the grommet provides a singlebody with a continuous surface including an elastomeric sealing surfacefor sealing with the access structure, an elastomeric surface forsealing with the check valve in the bore, and an exposed elastomericsurface for sealing with an exterior purging nozzle.
 12. A substratecontainer, comprising: an enclosure portion; and a cover portion adaptedto establish a fluid-tight engagement with the enclosure portion anddefine an interior volume; wherein at least one of the cover portion andthe enclosure portion has at least one access structure including atleast one of a fluid inlet, a fluid outlet, and a fluid vent; whereinthe at least one access structure retains a grommet formed ofelastomeric material in sealing communication therewith by way ofengagement of the elastomeric material with the access structure;wherein the grommet includes a fluid passageway with a bore surface ofelastomeric material that retains a check valve in sealing communicationwith the elastomeric material of the bore surface; and wherein thegrommet has a generally cylindrical shape with the fluid passagewayconfigured as a cylindrical bore extending axially and a pair ofopposite planar end surfaces, the cylindrical bore having an axiallength that is greater than the length of the valve such that the valveis disposed completely within the cylindrical bore, wherein the oppositeplanar end faces are comprised of the elastomeric material, and whereinone of the opposite planar end faces is exteriorly exposed with respectto the substrate container thereby providing a purge nozzle engagementsurface and the other of the opposite planar end faces confronts anapertured wall of the access structure with a filter positioned betweenthe apertured wall and the other of the opposite planar end faces,whereby the grommet provides a single body with a continuous surfaceincluding an elastomeric sealing surface for sealing with the accessstructure, an elastomeric surface for sealing with the check valve inthe bore, and an exposed elastomeric surface for sealing with anexterior purging nozzle.
 13. The substrate container of claim 12,wherein the cover portion has a plurality of access structures each witha respective grommet as described in claim
 12. 14. The substratecontainer of claim 12, wherein the at least one access structureincludes a flow conduit having an inner surface against which thegrommet is in sealing communication.
 15. The substrate container ofclaim 12, wherein the grommet is adapted to facilitate a sealingengagement between a vacuum/fluid source and the interior volume of thesubstrate container.
 16. The substrate container of claim 12, whereinone of the planar end surfaces of the grommet is an exteriorly exposedsurface that provides a sealing surface for a nozzle or nipple as partof a purging system without using o-rings.